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At least 271 records · Page 15

Absolute Ethanol Embolization of Arteriovenous Malformations in the Periorbital Region

ObjectiveArteriovenous malformations (AVMs) involving the periorbital region are technically challenging clinical entities to manage. The purpose of the present study was to present our initial experience of ethanol embolization in a series of 16 patients with auricular AVMs and assess the outcomes of this treatment.MethodsTranscatheter arterial embolization and/or direct percutaneous puncture embolization were performed in the 16 patients. Pure or diluted ethanol was manually injected. The follow-up evaluations included physical examination and angiography at 1- to 6-month intervals.ResultsDuring the 28 ethanol embolization sessions, the amount of ethanol used ranged from 2 to 65 mL. The obliteration of ulceration, hemorrhage, pain, infection, pulsation, and bruit in most of the patients was obtained. The reduction of redness, swelling, and warmth was achieved in all the 16 patients, with down-staging of the Schobinger status for each patient. AVMs were devascularized 100 % in 3 patients, 76–99 % in 7 patients, and 50–75 % in 6 patients, according to the angiographic findings. The most common complications were necrosis and reversible blister. No permanent visual abnormality was found in any of the cases.ConclusionEthanol embolization is efficacious and safe in the treatment of AVMs in the periorbital region and has the potential to be accepted as the primary mode of therapy in the management of these lesions.

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Role and Effectiveness of Percutaneous Arterial Embolization in Hemodynamically Unstable Patients with Ruptured Splanchnic Artery Pseudoaneurysms

PurposeTo assess the role and effectiveness of percutaneous arterial embolization (TAE) in patients with hemodynamic instability due to hypovolemic shock secondary to ruptured splanchnic artery pseudoaneurysms (SAPA).Materials and MethodsSeventeen patients (11 men, 6 women; mean age, 53 years) with hemodynamic instability (systolic blood pressure <90 mmHg) due to hypovolemic shock secondary to ruptured SAPA were treated by TAE. Clinical files, multidetector row computed tomography angiography, and angiographic examinations along with procedure details were reviewed.ResultsSeventeen SAPAs were present, predominantly located on gastroduodenal or pancreatic arteries (9/17; 53 %). Angiography showed extravasation of contrast medium from SAPA in 15/17 patients (88 %). Technical success rate of TAE was 100 %. TAE was performed using metallic coils in all patients (100 %), in association with gelatin sponge in 5/17 patients (29 %). TAE allowed controlling the bleeding and returning to normal hemodynamic status in 16/17 patients (94 %). In 1/17 patient (6 %), surgery was needed to definitively control the bleeding. The mortality and morbidity rate of TAE at 30 days were 0 and 12 %, respectively. Morbidity consisted in coil migration in 1/17 patient (6 %) and transient serum liver enzyme elevation in 1/17 patient (6 %).ConclusionTAE is an effective and safe treatment option for ruptured SAPA in hemodynamically unstable patients, with a success rate of 94 %. Our results suggest that TAE should be the favored option in patients with hemodynamic instability due to ruptured SAPA.

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Outcomes of Locoregional Tumor Therapy for Patients with Hepatocellular Carcinoma and Transjugular Intrahepatic Portosystemic Shunts

PurposeLocoregional therapy for hepatocellular carcinoma (HCC) can be challenging in patients with a transjugular intrahepatic portosystemic shunt (TIPS). This study compares safety and imaging response of ablation, chemoembolization, radioembolization, and supportive care in patients with both TIPS and HCC.MethodsThis retrospective study included 48 patients who had both a TIPS and a diagnosis of HCC. Twenty-nine of 48 (60 %) underwent treatment for HCC, and 19/48 (40 %) received best supportive care (i.e., symptomatic management only). While etiology of cirrhosis and indication for TIPS were similar between the two groups, treated patients had better baseline liver function (34 vs. 67 % Child-Pugh class C). Tumor characteristics were similar between the two groups. A total of 39 ablations, 17 chemoembolizations, and 10 yttrium-90 radioembolizations were performed on 29 patients.ResultsAblation procedures resulted in low rates of hepatotoxicity and clinical toxicity. Post-embolization/ablation syndrome occurred more frequently in patients undergoing chemoembolization than ablation (47 vs. 15 %). Significant hepatic dysfunction occurred more frequently in the chemoembolization group than the ablation group. Follow-up imaging response showed objective response in 100 % of ablation procedures, 67 % of radioembolization procedures, and 50 % of chemoembolization procedures (p = 0.001). When censored for OLT, patients undergoing treatment survived longer than patients receiving supportive care (2273 v. 439 days, p = 0.001).ConclusionsAblation appears to be safe and efficacious for HCC in patients with TIPS. Catheter-based approaches are associated with potential increased toxicity in this patient population. Chemoembolization appears to be associated with increased toxicity compared to radioembolization.

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Evaluation of Liver Stiffness After Radioembolization by Real-Time ShearWave™ Elastography: Preliminary Study

PurposeTo evaluate the effect of ShearWave™ elastography (SWE) for the assessment of liver fibrosis after radioembolization (RE) in patients with liver malignancies.Materials and MethodsWe prospectively examined the effects of SWE before and after RE in 17 adult patients, from June 2012 to September 2013. All patients underwent SWE within 1 month before and 3 months (96.3 ± 22.9 days) after RE. Measurements were taken in segments III, IV, V, and VI (lateral/medial left lobe and anterior/posterior right lobe, respectively). Liver stiffness was studied in the 39 treated segments.ResultsThe mean stiffness of liver tissue according to the pre-RE SWE measurements was not different from the post-RE SWE measurements in the segments that did not undergo RE. Conversely, segments treated with RE were significantly stiffer according to the post-RE SWE measurements (mean SWE 17.4 kPa) than according to the baseline measurements (7.0 kPa) (p < 0.001). Patients with hepatocellular carcinoma and preexisting infection with hepatitis B and C viruses had higher pre-embolization stiffness, and the post-embolization stiffness of the treated segments in these patients was higher than that in the remainder of the study population.ConclusionThese data suggest that SWE measurements of liver stiffness increase as early as the third month after RE. SWE could be used as a noninvasive complementary imaging method for preliminary assessment of liver fibrosis before and after RE.

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Impact of 3D Rotational Angiography on Liver Embolization Procedures: Review of Technique and Applications

In the last years, the interest into interventional applications of C-arm cone-beam CT (CBCT) progressively raised, widening its clinical application from the original field of interventional neuroradiology to the field of peripheral procedures. Liver embolization procedures, due to their complexity and potential treatment-related life-threatening complications, represent one of the main clinical applications of this novel angiographic technique. CBCT has been demonstrated to render procedures safer and technically easier, and to predict outcome as well as to avoid major complications in different treatment scenarios (trans-arterial embolization, trans-arterial chemoembolization, selective internal radiation therapy, percutaneous portal vein embolization). This review summarizes all technical, dosimetric and procedural aspects of CBCT techniques, underlying all its potential clinical advantages in the field of liver embolization procedures. Moreover, the paper provides all the instructions to obtain the best diagnostic performance out of this novel angiographic technique.

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Transarterial Chemoembolization for Hepatocellular Carcinomas with Central Bile Duct Invasion: Safety, Prognosis, and Predictive Factors

PurposeTo assess the safety and effectiveness of transarterial chemoembolization (TACE) of patients who have hepatocellular carcinomas (HCCs) with central bile duct invasion.Materials and MethodsThe institutional review board approved this retrospective study and waived informed consent. Fifty-three patients, initially treated with TACE for HCCs with central bile duct invasion from January 1999 to September 2012, were included. Clinical, laboratory, and survival data were reviewed. Complications and hospitalization length were evaluated using the χ{sup 2} test, Fisher’s exact test, and logistic regression analysis. Survival was analyzed using the Kaplan–Meier method with log-rank test and Cox proportional hazard model.ResultsSeven patients experienced TACE-related major complications (severe post-embolization syndrome in 3, non-fatal sepsis in 3, and secondary bacterial peritonitis in 1). The overall major complication rate was 13.2 %, but there were no permanent adverse sequelae or deaths within 30 days. Serum total bilirubin ≥3.0 mg/dL was the only significant risk factor for long hospitalization [hazard ratio (HR) = 4.341, p = .022]. The median survival was 12.2 months. Extrahepatic metastasis (HR = 6.145, p < .001), international normalized ratio (PT-INR) ≥1.20 (HR = 4.564, p < .001), vascular invasion (HR = 3.484, p = .001), and intermediate tumor enhancement (HR = 2.417, p = .019) were significantly associated with shorter survival.ConclusionTACE can be a safe and effective treatment for patients who have HCCs with central bile duct invasion. In particular, long-term survival can be expected if patients have strongly enhancing tumors without poor prognostic factors such as extrahepatic metastasis, PT-INR prolongation, and vascular invasion.

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Safety and Effectiveness of UFE in Fibroids Larger than 10 cm

IntroductionEarly literature suggested that the size of the uterus, the size of the dominant fibroid, and the amount of applied embolization particles would be the risk factors for major postprocedural complications, but recent publications have confuted these early results. The purpose of our study was to evaluate whether the size of the dominant fibroid would influence the complication rate and effectiveness in a large single-center cohort.Patients and MethodsFrom 28 April 2008 until 31 December 2012, 303 patients had uterine artery embolization (UAE). 262 patients had small [largest diameter <10 cm (Group 1)], 41 patients had large [largest diameter >10 cm (Group 2)] fibroid. UAE was performed from unilateral femoral access using 500–710 and 355–500 µm polyvinyl alcohol particles. Periprocedural and postprocedural complications and numerical analog quality-of-life scores (0—unbearable symptoms; 100—perfect quality of life) were listed and statistically analyzed.ResultsDuring the mean follow-up time [7.79 ± 5.16 (SD) month], data on 275 patients (275/303 = 90.8 %) were available. Quality-of-life score was 33.3 ± 23.5 and 33.5 ± 24.1 before, whereas 85.6 ± 16.0 and 81.5 ± 23.5 after UAE in Group 1 and Group 2, respectively, (Mann–Whitney U test one-sided, p = 0.365). There were 4 myoma expulsions, 1 acute myomectomy, and 2 acute hysterectomies reported from Group 1, meanwhile 1 myoma expulsion, 1 acute myomectomy, and 2 acute hysterectomies were documented from Group 2 (NS differences).ConclusionThere was no significant difference in the effectiveness and in the number of minor and major complications between fibroids with <10 cm largest diameter compared to those >10 cm.

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Transcatheter Arterial Embolization for Postpartum Hemorrhage: Indications, Technique, Results, and Complications

Postpartum hemorrhage (PPH) is a potentially life-threatening condition, which needs multidisciplinary management. Uterine atony represents up to 80 % of all causes of PPH. Transcatheter arterial embolization (TAE) has now a well-established role in the management of severe PPH. TAE allows stopping the bleeding in 90 % of women with severe PHH, obviating surgery. Pledgets of gelatin sponge as torpedoes are commonly used for safe TAE, and coils, glue, and microspheres have been primarily used in specific situations such as arterial rupture, pseudoaneurysm, and arteriovenous fistula. TAE is a minimally invasive procedure with a low rate of complications, which preserves future fertility. Knowledge of causes of PPH, potential risks, and limitations of TAE is essential for a timely decision, optimizing TAE, preventing irreversible complications, avoiding hysterectomy, and ultimately preserving fertility.

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Compatibility of an Ultraselective Microcatheter and Epirubicin Loaded 300–500-μm DC Bead in Ex Vivo Study

PurposeThe purpose of this study is to examine whether epirubicin loaded DC Bead 300–500 μm in size can pass through a 1.8-Fr ultraselective microcatheter in ex vivo study.MethodsEpirubicin (25 mg/1 mL) loaded 100–300 and 300–500 μm DC Bead were tested. Both sizes were diluted 5, 10, and 30 times using contrast material. Ultraselective microcatheter with the outer diameter of 1.8 Fr and the inner diameter of .017 inch (431.8 μm) was used. The diluted DC Bead was injected at a speed of 1 mL/min, and the pressure was continuously measured. The microspheres’ shapes after ejection were observed by a stereomicroscope.ResultsThe maximum pressure of contrast material alone was 8.40 ± 0.21 psi. The maximum pressure in 5, 10, and 30 times dilution groups of 100–300 μm were 9.67 ± 1.18, 9.25 ± 0.25, and 9.71 ± 0.28 psi, respectively, whereas 21.10 ± 10.2, 10.48 ± 2.14, 10.09 ± 0.37 psi, respectively in 300–500 μm groups. The maximum pressure in 5 times dilution group of 300–500 μm was significantly higher than the other groups (P < 0.05). In 300–500 μm, 4 of 10 measurements showed high pressure over 24 psi (the maximum value was 43.5 psi) in 5 times dilution group, whereas in 10 times and 30 times dilution groups, all measurements showed less than 12 psi. No damages of microspheres were found.ConclusionsEpirubicin loaded DC Bead 300–500 μm in size can pass through a 1.8-Fr ultraselective microcatheter. To avoid high resistance due to microspheres’ aggregation, dilution more than 10 times is needed.

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Cranial Nerve Dysfunction Associated with Cavernous Dural Arteriovenous Fistulas After Transvenous Embolization with Onyx

PurposeCranial nerve dysfunction (CND) is not uncommon in patients with cavernous dural arteriovenous fistulas (cDAVFs), and may represent an initial manifestation or a complication after endovascular treatment. This study evaluated the outcome of CND associated with cDAVFs after transvenous embolization (TVE) using Onyx.Materials and MethodsForty-one patients with cDAVFs were treated with TVE in our department between April 2009 and October 2013. For each patient, clinical and radiologic records were retrospectively reviewed and evaluated, with an emphasis placed on evaluating the outcomes of the pre-existing cDAVF-induced CND and the TVE-induced CND.ResultsOf the 41 cases, 25 had a history of preoperative CND. Postoperatively, gradual remission to complete recovery (CR) within 8 months was observed in 17 of these cases, transient aggravation in 7, and significant improvement to be better than preoperative function but no CR in 1. All aggravation of CND occurred immediately or within 1 day after TVE and resolved completely within 5 months. Nine patients developed new CND after TVE. New CND occurred during the perioperative period in 8 cases, but all cases resolved completely within 15 days–6 months. Delayed CND was observed in 3 cases with a time lag of 3–25 months after TVE. Two of these completely resolved within 20 days–1 month and the remaining case significantly improved.ConclusionBoth the pre-existing cDAVF-induced CND and the TVE-induced new or aggravated CND completely resolved in almost all cases after embolization with Onyx.

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The Retrograde Transvenous Push-Through Method: A Novel Treatment of Peripheral Arteriovenous Malformations with Dominant Venous Outflow

PurposeTo evaluate the efficacy and safety of a novel retrograde transvenous embolization technique of peripheral arteriovenous malformations (AVMs) using Onyx.Materials and MethodsWe conducted a retrospective analysis of all patients who underwent transvenous retrograde Onyx embolization of peripheral AVMs with dominant venous outflow over a 29-month period. The embolization is aimed at retrograde filling of the nidus after building a solid plug in the dominant venous outflow (push-through). Classification, clinical signs, technical aspects, clinical and technical success rates, and complications were recorded. Short-term outcome was assessed.Results11 Symptomatic patients (8 female; mean age 31.4 years) were treated at our Vascular Anomalies Center with this method between January 2012 and May 2014. The AVMs were located on the upper extremity (n = 3), pelvis (n = 2), buttock (n = 2), and lower extremity (n = 4). Retrograde embolization was successfully carried out after preparatory transarterial-flow reduction in eight cases (73 %) and venous-flow reduction with Amplatzer Vascular Plugs in four cases (36 %). Complete devascularization (n = 10; 91 %) or 95 % devascularization (n = 1; 9 %) led to complete resolution (n = 8; 73 %) or improvement of clinical symptoms (n = 3; 27 %). One minor complication occurred (pain and swelling). During a mean follow-up time of 8 months, one clinically asymptomatic recurrence of AVM was detected.ConclusionInitial results suggest that retrograde transvenous Onyx embolization of peripheral AVMs with dominant venous outflow is a safe and effective novel technique with a low complication rate.

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Embolization by Direct Puncture with a Transpedicular Approach Using an Isocenter Puncture (ISOP) Method in a Patient with a Type II Endoleak After Endovascular Aortic Repair (EVAR)

BackgroundEndovascular aortic repair (EVAR) requires further intervention in 20-30 % of cases, often due to type II endoleak (T2EL). Management options for T2EL include transarterial embolization, direct puncture (DP), or transcaval embolization. We report the case of an 80-year-old man with T2EL who successfully underwent DP embolization.MethodsEmbolization by DP was performed with a transpedicular approach using an isocenter puncture (ISOP) method. An isocenter marker (ICM) was placed at a site corresponding to the aneurysm sac on fluoroscopy in two directions (frontal and lateral views). A vertebroplasty needle was inserted tangentially to the ICM under fluoroscopy and advanced to the anterior wall of the vertebral body. A 20 cm-length, 20-G-PTCD needle was inserted through the outer needle of the 13-G needle and advanced to the ICM. Sac embolization using 25 % N-buty-2-cyanoacrylate diluted with Lipiodol was performed. After complete embolization, rotational DA confirmed good filling of the sac with Lipiodol. The outer cannula and 13-G needle were removed and the procedure was completed.ResultsThe patient was discharged the next day. Contrast-enhanced computed tomography 1 and 8 months later showed no Lipiodol washout in the aneurysm sac, no endoleak recurrence, and no expansion of the excluded aneurysm.ConclusionDP with a transpedicular approach using ISOP may be useful when translumbar and transabdominal approaches prove difficult.

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Female Pelvic Vein Embolization: Indications, Techniques, and Outcomes

Until recently, the main indication for pelvic vein embolization (PVE) in women was to treat pelvic venous congestion syndrome (PVC) but increasingly, patients with refluxing pelvic veins associated with leg varicosities are also being treated. A more unusual reason for PVE is to treat pelvic venous malformations, although such lesions may be treated with sclerotherapy alone. Embolotherapy for treating PVC has been performed for many years with several published studies included in this review, whilst an emerging indication for PVE is to treat lower limb varicosities associated with pelvic vein reflux. Neither group, however, has been subjected to an adequate randomized, controlled trial. Consequently, some of the information presented in this review should be considered anecdotal (level III evidence) at this stage, and a satisfactory ‘proof’ of clinical efficacy remains deficient until higher-level evidence is presented. Furthermore, a wide range of techniques not accepted by all are used, and some standardization will be required based on future mandatory prospective studies. Large studies have also clearly shown an unacceptably high recurrence rate of leg varicose veins following venous surgery. Furthermore, minimally or non-invasive imaging is now revealing that there is a refluxing pelvic venous source in a significant percentage of women with de novo leg varicose veins, and many more with recurrent varicosities. Considering that just over half the world’s population is female and a significant number of women not only have pelvic venous reflux, but also have associated leg varicosities, minimally invasive treatment of pelvic venous incompetence will become a common procedure.

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Radiodermitis After Prostatic Artery Embolization: Case Report and Review of the Literature

Prostate artery embolization (PAE) is a technically demanding new treatment option for benign prostatic hyperplasia. We present a case of radiation-induced dermitis in a 63-year-old patient after a technically successful PAE, due to high radiation exposure (KAP: 8,023,949 mGy cm{sup 2}) and long fluoroscopy time (72 min). Anatomical and technical aspects are discussed, as well as recommendations to decrease radiation exposure in these procedures.

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